Elizabeth Edwards, the estranged wife of former Democratic presidential candidate John Edwards, has died after a lengthy battle with cancer.

Her family had issued a statement saying doctors had told Edwards that further treatment for her cancer would be unproductive.

She spent her last days at home in the state of North Carolina with family and friends gathered.

Edwards, a lawyer, supported her husband's political ambitions as he served as a U.S. senator and ran for president in 2008.

She left the marriage, but did not seek a divorce, when it was revealed that her husband had fathered a child after an affair with a campaign worker.

Mrs. Edwards was diagnosed with breast cancer on Election Day 2004 -- the same day her husband, the vice-presidential nominee to presidential nominee John Kerry, lost the election to incumbent George W. Bush.

U.S. Vice-President Joseph Biden called her "inspiration to all who knew her."